: "Think of a sheet of glass set out to capture the sunlight instead of letting the light pass through or reflecting it off somewhere, it captures the light inside the thickness of the pane. It then redirects it toward an edge, or a number of them, where it then emerges at a concentration ratio directly related to the square area of the collector surface and the square area of the interfaces it emerges from. It can actually do a lot more for instance, the collected radiant energy could emerge from the entire length of an edge, similar to a parabolic trough line-focus. However, it is possible to have it emerge from only a specific section of an edge - the equivalent of a point focus. In addition collected radiant energy can be passed through from one device to another."

The Lateral Aperture concept was the first design for a solar collector with built-in tracking and internal concentration of collected energy. Its development was the result of research conducted in the 1980s to develop a practical solar energy cooking system appropriate for refugee and rural populations in tropical areas facing shortages of traditional firewood supplies.

However, the concept is so basic in nature that it's unique characteristics also makes it highly adaptable for use not only in Solar Concentration applications, but in other radiant energy fields such as Fiber Optics.

The Lateral Aperture design concept, with its more sophisticated internal collection, concentration, and routing capabilities, is directly competitive with current dichroic dye base Solar Concentration technology in Solar PVC applications.

About

Official Website

http://research.atspace.org

How it Works

Abstract: A design for a wave-transmission device with a collection surface (aperture) parallel (lateral) to the internal transmission path of the collected radiant energy. Elimination of shadowing effects allows for internal concentration of collected radiant energy, and the use of modular components for scaling up system capabilities. Internal processing of radiant energy permits variations in external shapes and forms. For instance, the collection surface may be flat, curved, or spherical allowing for input from nearly any angle, with a wide angle of acceptance, which is the equivalent in solar applications of possessing built-in tracking capabilities with no moving parts. Output may occur at single or multiple surfaces, may be the equivalent of point-focus, line-focus, or combinations of both, and may occur at nearly any angle. Devices based on this design are potentially directly competitive with parabolic reflectors and lens refraction systems. Potential market applications might include, but not be limited to: solar concentrators fiber-optic multi-signal input / output devices land based micro-wave transmission and broadcast satellite reception antenna.

Advantages

Solar Concentrators

Tracking Systems: The Lateral Aperture design basically does away with tracking systems, which as a rule of thumb can account for roughly up to 50% of a solar concentrating system's overall construction costs, and 80% of operational maintenance costs.

Energy Transport Systems: Internal beam control and routing capabilities would mean that in Solar Thermal applications the use of energy wave-guide transport systems could be used, which operate at over 95% efficency. This would eliminate fluid transport systems, a major source of heat losses, plus their construction, operation, and maintenance costs.

Modular Construction: Radiant energy pass-through capability allows for the use of standard modular elements. This would provide for extreme flexibility in meeting sizing requirements in a cost effective manner plus allowing the size of systems to be easily scaled up or down to meet changing requirements.

Structural Stability: Lateral Aperture designs with their thin form factor, ability to utilize curved surface collectors, and lack of tracking mechanisms would be inherently stable and highly resistant to damage from destructive winds or other forces.

Fiber Optics

Alignment: Lateral Aperture based input surfaces could be an order of size larger than that of Optic Fiber diameters, and could be positioned at almost any angle, including 90 degrees, to the axial plane of the fiber. This could potentially greatly alleviate alignment errors which are a major problem in introducing signals and in making splices and couplings.

Multi-Function Modules: Lateral Aperture designs have the potential capability to combine within a single module the functions of a prism, lens, grating, and / or mirror, thus greatly simplifying the process and associated cost of inputing signals, making splices, or adding couplings. In addition signals can be introduced without blocking the passage of signals already in transit.

Applications

Solar Concentrators

Photo-Voltaic: The development over the last decade of higher temperature higher efficiency photo-voltaic cells has generated increased interest in incorporating solar concentrating devices within photo-voltaic systems to increase output and lower costs. The built-in self-tracking capabilities, zero focal length, internal concentration and routing of solar energy, structural resistance to environmental forces, and the ability to provide line focus or point focus delivery of radiant energy makes the Lateral Aperture design concept highly adaptable to photo-voltaic applications.

Absorption Refrigeration: Air conditioning is a major peak-load demand on conventional power systems it is also a direct function of solar insolation which makes it a prime candidate for solar derived answers. In addition, absorption refrigeration systems are proven, reliable, rugged systems which operate directly from the application of heat between 90 - 150 C (200 - 300 F). Solar refrigeration systems, however, have traditionally suffered from high cost and reliability problems generally associated with their tracking systems. The integration of Lateral Aperture design based concentrating systems could potentially eliminate the majority of expenses related to tracking system maintenance and heat transport losses, thus making solar absorption refrigeration systems economically viable.

Solar Cooking / Thermal: This was the principal area of interest which motivated the research behind the Lateral Aperture design concept it is, however, a low value market which hasn't attracted much interest in academic or industry circles. The traditional target group for solar cookers has been the rural poor therefore, cost concerns have dictated a parsimony which results in designs that do not meet needs. Traditional flat plate cookers do not offer an adequate temperature range to address normal cooking demands, and are marginal at best even as a rice steamer. Solar boxes using reflective flats do not provide for frying they require manual alignment cooking must be done on site while the sun is out and high gusty winds can cause damage. Parabolic devices simply require too much money and maintenance to make them practical. Most deployed in large scale field projects have been inexpensive flimsy portable units which had to be moved under shelter if the wind blew or it rained. They required manual adjustment and required constant attention as their alignment requirements were critical. Cooking had to be done on site while the sun shined, thus often disrupting normal traditional routines.

: The Lateral Aperture design was conceived specifically for use with solar cooking systems that are culturally, environmentally, and technologically appropriate. It has high resistance to environmental forces, such as high winds and gusts. Internal routing capabilities integrate seamlessly with light guide energy transport systems which allow for dispersed placement of system components for instance collectors can be elevated while the cooking units are under shelter. Modular constructions allows for ease in meeting sizing requirements. A practical dual wall semi-evacuated heat storage component, utilizing cheap iron pellets immersed in oil in the interior chamber, can be made out of rugged LPG high pressure containers nested together. Collected solar energy would be fed into the interior from the light guide through high temperature glass ports in the base. The entire system would be sealed, and maintanence would consist primarily of keeping the collector surface clean. High temperatures would provide for a complete range of cooking needs from frying to steaming. In addition, integrated water heating components could be constructed for the production of hot water, distillation of potable drinking water, etc.

Fiber Optics

Multiplexers: The combination of large input surfaces, multiple angles and planes of orientations, together with point-focus output, for all practical purposes removes restrictions, such as limits on the size and number of input sources, and other difficulties encountered in combining signals from multiple sources.

Couplers: The Lateral Aperture's capability to handle large alignment errors could mitigate many of the problems associated with traditional industry splicing and coupling techniques.

Business Model

Profitable commercialization of this technology would more than likely take place in the Fiber Optic and Solar PVC fields. The purpose of this page at PESWiki is to help identify individuals and/or organizations specializing in R&D efforts required to take innovative concepts through to commercialization. Serious queries by such parties are welcome.

The inventor's interest is primarily centered on the Solar Cooking aspects. While this might eventually develop a profitable manufacturing and marketing model, the idea for now is to conduct such activities under the umbrella of a non-profit grass-roots development organization.